Federal officials say the tunnel stretches from Tijuana, Baja California, Mexico to Otay Mesa, about 500 yards north of the U.S.-Mexico border.

The 800-yard tunnel route begins at a house in Tijuana, Mexico, and ends in the Otay Mesa neighborhood of San Diego.

Agents were hot on the tail of thealleged drug traffickers after they noticed a commercial truck deliver an industrial dumpster filled with wood scraps to an outdoor industrial lot; days later, agents discovered this to be an entryway into the tunnel.

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The tunnel was furnished with ventilation systems, lights and even a large elevator that led into a closet inside the Tijuana residence, officials said.

The tunnel exit on the U.S. side is a 3-foot-diameter hole that was covered by an industrial dumpster.

"On the surface, few would ever suspect that traffickers were moving multiton quantities of cocaine and marijuana worth tens of millions of dollars in such an unassuming way, through this rabbit hole in the ground, in full view of the world around it," said U.S. Attorney Laura Duffy in the release.

The six people were arrested in San Diego and charged with various drug trafficking charges, police said.

"This case is a strong reminder of the vulnerabilities that exist along the Southwest border," said Hunter Davis, director of air operations for Customs and Border Protection, Air and Marine Operations.